JP2001145241A - Wiring board assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board assembly that prevents molding failure of an insulating board and is capable of being assembled with reliability. SOLUTION: Protruded bosses 46 to 48 for caulking are formed on insulating boards 24 to 26 formed out of synthetic resin. Boss releasing recesses 55 to 57 for housing the ends 49 to 51 of the bosses 46 to 48 formed on other laminated insulating boards 24 to 26 are formed on the insulating boards 25 to 27. The boss releasing recesses 55 to 57 become deeper as they go from the peripheral portion toward the center. Bus bars 28 to 31 are placed between the insulating boards 24 to 27. Insertion holes 52 to 54 are formed in the bus bars 29 to 31. The bosses 46 to 48 are inserted into the insertion holes 52 to 54 and caulked, thereby securing the bus bars 29 to 31 on the insulating boards 24 to 27 and assembling a wiring board assembly 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board assembly.

[0002]

2. Description of the Related Art Conventionally, there is known an electric junction box in which a wiring board assembly is housed. The wiring board assembly is used as a connection branch point for wiring such as a wire harness.

[0003] For example, as shown in FIG. 6, insulating substrates 72 constituting a part of a wiring board assembly 71 are laminated.
A bus bar 76 is arranged between the two insulating substrates 72. The insulating substrate 72 is formed of a synthetic resin.
A caulking boss 73 is formed on the insulating substrate 72 so as to protrude. At the same time, the tip 74 of the boss 73 provided on the insulating substrate 72 is accommodated in a boss relief 75 recessed in another insulating substrate 72. The bus bar 76 has an insertion hole 77.

In order to assemble the insulating substrate 72 and the bus bar 76, first, the boss 73 is inserted through an insertion hole 77 provided in the bus bar 76. In that state, the boss 7
3 is crimped. As a result, the bus bar 76 is fixed to the insulating substrate 72. The wiring board assembly 71 is configured by alternately stacking the insulating substrates 72 and the bus bars 76.

[0005] The wiring board assembly 71 is housed in a lower case 78. In this state, the engagement protrusion 80a provided on the lower case 78 is fitted into the engagement recess 80b provided on the upper case 79. As a result, the lower case 78
, The upper case 79 is fixed.

[0006]

However, as shown in FIG. 7, when the tip 74 of the boss 73 is not completely swaged, the tip 74 comes into contact with the inner wall surface of the boss relief 75. . Therefore, the insulating substrate 72 and the bus bar 7
6 is generated.
Therefore, the portion (tab) where the bus bar 76 protrudes from the upper surface of the insulating substrate 72 is easily shortened. Therefore, the bus bar 76 and the connector (not shown) may have a poor fitting. In addition, the lower case 78 and the upper case 7
9 cannot be fitted using the engaging projection 80a and the engaging recess 80b. Therefore, in order to solve those problems, the boss relief 75 tends to be formed deeply.

[0007] However, as shown in FIG.
In order to form the insulating substrate 72 by pouring the resin 82 into the metal mold 81 to form
Was not completely filled in the mold 81 in some cases. As a result, a short shot may occur at a portion that should be the bottom of the boss relief 75, and the insulating substrate 72 may be defectively formed. For the above reasons, the depth of the boss escape 75 could not be sufficiently set.

Further, since the thickness of the bus bar 76 is smaller than the interval between the insulating substrates 72, the tip 7
Insulating substrates 7 adjacent to each other regardless of the caulking condition of 4
There was a problem that a gap was formed between the two. For this reason, the insulating substrate 72 and the bus bar 76 may rattle and generate abnormal noise.

The present invention has been made in view of the above problems, and an object of the present invention is to prevent molding defects of an insulating substrate,
An object of the present invention is to provide a wiring board assembly that can be securely assembled.

[0010]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, a boss for caulking is formed protrudingly on an insulating substrate which is a resin molded product and laminated on the insulating substrate. A boss relief for accommodating the tip of the boss is recessed in another insulating substrate, and the boss is inserted into an insertion hole formed in a bus bar located between the two insulating substrates and swaged to form a boss. By fixing the bus bar to the insulating substrate, in the wiring board assembly in which the insulating substrate and the bus bar are assembled, the boss relief is gradually deepened from the outer peripheral portion toward the central portion. The gist is that it is recessed.

[0011] The gist of the present invention is that the outer periphery of the bottom surface of the boss relief is a tapered surface. According to the third aspect of the present invention, a concave portion for accommodating a bus bar having a terminal piece in a part thereof is provided on the insulating substrate, and the depth of the concave portion is equal to the thickness of the bus bar. .

The "action" of the present invention will be described below. According to the first aspect of the present invention, the boss relief is recessed so as to be gradually deeper from the outer peripheral portion toward the central portion. So even if you make a deep boss escape,
The bottom of the boss relief is completely filled with the resin, thereby preventing occurrence of a short shot during molding. Therefore,
It is possible to reliably assemble the wiring board assembly by preventing molding defects of the insulating substrate.

According to the second aspect of the present invention, since the outer peripheral portion of the bottom surface of the boss relief is a tapered surface, the occurrence of a short shot is prevented while the boss relief depth is sufficiently secured. Therefore, the tip of the boss is securely inserted into the boss relief, and the insulating substrates are brought into close contact with each other. Therefore, the wiring board assembly can be assembled more reliably.

According to the third aspect of the present invention, since the depth of the concave portion and the thickness of the bus bar are formed to have the same size, the bus bar and the insulating substrate are in close contact with each other. Therefore, the wiring board assembly can be reliably assembled. Further, generation of abnormal noise due to rattling between the insulating substrate and the bus bar can be prevented.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electric junction box according to an embodiment of the present invention will now be described in detail with reference to FIGS.

As shown in FIG. 1, the electric connection box 11 is formed of a synthetic resin, and includes an upper case 12 and a lower case 13. The upper case 12 and the lower case 13 are locked and held by the engagement of an engagement protrusion 14 and an engagement recess 15 provided on a part of the outer peripheral wall.

On the upper surface of the upper case 12, a rectangular cylindrical connector housing 16 is formed. A plurality of tab insertion holes 17 are provided through the bottom surface of the connector housing 16. The lower case 13 has a bottom 18a and a peripheral wall 18b.
A wiring board assembly 19 is accommodated in the lower case 13. The wiring board assembly 19 includes a plurality of wiring boards 2.
0, 21, 22, and 23 are stacked. The inner surface of the bottom portion 18a supports the lowermost wiring board 20.

As shown in FIG. 1 and FIG.
23 are insulating substrates 24, 25, 2 made of a synthetic resin material.
6, 27, and bus bars 28, 29, 30, 3 made of a metal plate disposed on the lower surface side of these insulating substrates 24 to 27.
And 1.

Insulating ribs 32, 33, 34, and 35 are formed on the lower surfaces of the peripheral edges of the insulating substrates 24 to 27 so as to protrude. A concave portion 36 is formed on the lower surface of the insulating substrate 24 to 27 by the insulating ribs 32 to 35. The bus bars 28 to 31 are housed in the recess 36.
As shown in FIG. 2, the depth A1 of the recess 36 is
It is set to the same size as the thickness A2 of ~ 31. Therefore, the insulating substrates 24 to 27 and the bus bars 28 to 31 are in close contact with each other.

Tabs 38, 39, 40, and 4 as terminal strips are provided at predetermined locations of the bus bars 28 to 31, respectively.
1 is bent upward. Multiple tabs 38
The lengths of the tabs 41 to 41 are set such that the tips of the tabs 38 to 41 have the same height when the wiring boards 20 to 23 are stacked and accommodated. Therefore, the tab 41 of the uppermost bus bar 31 is the shortest, and the tab 38 of the lowermost bus bar 28 is the longest. These tabs 38 to 41 are respectively inserted into a plurality of tab insertion holes 17 provided in the connector housing 16.

A through-hole 42 is provided at a position corresponding to the tab 38 on the insulating substrate 24. A plurality of through-holes 43 are provided at positions corresponding to the plurality of tabs 38 and 39 on the insulating substrate 25, respectively. A plurality of through-holes 44 are respectively provided at positions corresponding to the plurality of tabs 38 to 40 on the insulating substrate 26.
Further, a plurality of through-holes 45 are respectively provided at positions corresponding to the plurality of tabs 38 to 41 on the insulating substrate 27.

On the upper surfaces of the insulating substrates 24 to 26, bosses 46, 47 and 48 for caulking are formed so as to protrude. Boss 4
The tip portions 49, 50, 51 of 6 to 48 are caulked. Then, the bus bar 29 is arranged so as to correspond to the boss 46.
Is provided with a through hole 52. Tip 4 of boss 46
A boss relief 55 is formed in the concave portion 36 of the insulating substrate 25 so as to correspond to 9. The boss 4 is inserted into the insertion hole 52.
6, the bus bar 29 is fixed to the insulating substrate 25 by caulking the tip portion 49.

An insertion hole 53 is formed in the bus bar 30 so as to correspond to the boss 47. A boss relief 56 is formed in the recess 36 of the insulating substrate 26 so as to correspond to the tip 50 of the boss 47. By inserting the boss 47 into the insertion hole 53 and caulking the tip 50,
Bus bar 30 is fixed to insulating substrate 26.

Further, an insertion hole 54 is provided in the bus bar 31 so as to correspond to the boss 48. The concave portion 36 of the insulating substrate 27 corresponds to the tip portion 51 of the boss 48.
Is provided with a boss relief 57. This insertion hole 54
The bus bar 31 is fixed to the insulating substrate 27 by inserting the boss 48 into the boss 48 and caulking the end portion 51.

These boss reliefs 55 to 57 are recessed so as to gradually become deeper from the outer periphery to the center. The width of the boss relief 55-57 is the boss 46
It is larger than the size of the outer diameter of ~ 48. The depth of the boss reliefs 55 to 57 is larger than the height of the tip portions 49 to 51. The outer periphery of the bottom surface of the boss reliefs 55 to 57 is a tapered surface 58. Insulating substrate 25-27
In (2), the thickness of the central portion of the bottom surface of the boss relief 55-57 is about one third of the thickness of the insulating substrates 25-27. The thickness of the outer peripheral portion of the bottom surface of the boss relief 55 to 57 is about one third to two thirds of that of the insulating substrates 25 to 27. The tapered surface 58 is inclined by about 45 ° with respect to the bottom surfaces of the boss reliefs 55 to 57. For these reasons, the synthetic resin is completely filled at the time of molding the insulating substrates 25 to 27, and the occurrence of short shots at the time of molding is prevented. Also, the tip portions 49 to 51 of the bosses 46 to 48 are securely inserted into the boss reliefs 55 to 57, and the respective insulating substrates 24 to 27 are brought into close contact with each other.

Therefore, as shown in FIG.
8 to 41 are inserted into the corresponding through holes 42 to 45, respectively. The bosses 46 to 48 are inserted into the corresponding boss reliefs 55 to 57, respectively. Therefore, the wiring boards 20 to 23 of each layer are accommodated in the lower case 13 in a stacked state.

Next, the process of forming the insulating substrates 25 to 27 will be described in detail. As shown in FIGS. 3A and 3B,
A protrusion P1 is provided on the inner surface of the mold 61. In order to form the insulating substrates 25 to 27, first, as shown in FIG. 3A, a molten resin 62 is injected into a mold 61. The resin 62 includes a protrusion P protruding from the inner surface of the mold 61.
The first portion 63 and the tapered portion 64 are smoothly injected in the direction of the central portion 65. As shown in FIG. 3B, when the resin 62 is filled in the mold 61, the resin 62
Wait until is set. After the resin 62 has hardened, the mold 61 is opened in the direction of arrow F1. As a result, the insulating substrates 25 to 27 are formed of the resin 62.

Therefore, according to the present embodiment, the following effects can be obtained. (1) The boss reliefs 55 to 57 are recessed so as to gradually become deeper from the outer periphery toward the center. for that reason,
At the time of molding the insulating substrates 25 to 27, the synthetic resin is completely filled, and the occurrence of short shots is prevented. Therefore, molding defects of the insulating substrates 25 to 27 can be prevented. Therefore, the wiring boards 20 to 23 of the respective layers are brought into close contact with each other. Therefore, the wiring board assembly 19 can be reliably assembled. This wiring board assembly 19 is securely accommodated in the lower case 13. Therefore, the upper case 12 can be securely attached to the lower case 13 by engaging the engaging protrusion 14 and the engaging recess 15.

(2) The boss reliefs 55 to 57 are tapered at the outer periphery of the bottom surface of the boss reliefs 55 to 57.
The occurrence of short shots is prevented with a sufficient depth of 7. Therefore, the tip 4 of the bosses 46 to 48
9 to 51 are surely inserted into the boss reliefs 55 to 57, and the insulating substrates 24 to 27 are adhered to each other. Therefore, the wiring board assembly 19 can be assembled more reliably. Further, the presence of the tapered surface 58 reduces the area of the thick portions of the insulating substrates 25 to 27. Therefore,
The strength of the insulating substrates 25 to 27 can be secured.

(3) Depth A1 of recess 36 and bus bar 28
The thicknesses A2 to 31 are formed in the same size.
Therefore, when the wiring board assembly 19 is configured, the bus bars 28 to 31 and the insulating substrates 24 to 27 are in close contact with each other, and no gap is generated. Therefore, the wiring board assembly 19 can be reliably assembled. Further, it is possible to prevent generation of abnormal noise due to rattling between the insulating substrates 24 to 27 and the bus bars 28 to 31.
Further, tabs 38 projecting into connector housing 16
The length of ~ 41 is always stable. Therefore, the tabs 38 to 41
There is no need to allow extra length. Therefore, even if the tabs 38 to 41 are shortened, the connector can be securely fitted.

The embodiment of the present invention may be modified as follows. In the above-described embodiment, the bosses 46 to 48 correspond to the insulating substrates 24 to
26, and the boss reliefs 55-57 are recessed on the lower surfaces of the insulating substrates 25-27. On the other hand,
As shown in FIG. 5, bosses 47, 47a, 48, and 48a are provided on the upper and lower surfaces of the insulating substrates 25 and 26, respectively. Then, the boss reliefs 56a and 57a are recessed on the upper surfaces of the insulating substrates 24 and 25. At the same time, the boss escaped 56,5
7 may be recessed on the lower surfaces of the insulating substrates 26 and 27.

In the above embodiment, the depth A1 of the concave portion 36
And the thickness A2 of the bus bars 28 to 31 were formed in the same size. On the other hand, the depth A1 of the concave portion 36 may be formed smaller than the thickness A2 of the bus bars 28 to 31. With this configuration, the insulating ribs 32 to 3
5, the length of each becomes shorter. Therefore, the insulating substrates 24 to
27 can be reduced in manufacturing cost.

In the above embodiment, the boss escapes 55-5
7 is recessed so as to gradually become deeper from the outer peripheral portion to the central portion. And boss escape 55-
The outer peripheral portion of the bottom surface of 57 is a tapered surface 58. On the other hand, as shown in FIG. 4, the boss reliefs 55 to 57 may be formed in a semicircular cross section.

In the above embodiment, the bosses 46 to 48
The diameter of the tip portions 49 to 51 of the boss relief 55 to 5
7 was formed smaller than the inside diameter. On the other hand,
The diameter of the tip portions 49 to 51 may be formed to be the same size as the inner diameter of the boss relief 55 to 57. With such a configuration, rattling between the insulating substrates 24 to 27 can be prevented.

Next, in addition to the technical ideas described in the claims, technical ideas grasped by the above-described embodiment will be enumerated below. (1) A boss for caulking is formed protrudingly on an insulating substrate which is a resin molded product, and a boss relief for accommodating the tip of the boss is formed in another insulating substrate laminated on the insulating substrate, By inserting the boss into an insertion hole formed in the bus bar located between the two insulating substrates and caulking, the bus bar is fixed to the insulating substrate,
In the wiring board assembly in which the insulating substrate and the bus bar are assembled, a thickness of a bottom portion of the boss relief is formed so as to gradually decrease from an outer peripheral portion to a center portion of the boss relief. Characteristic wiring board assembly.

(2) The wiring board assembly according to any one of claims 1 to 3, wherein a diameter of a tip portion of the boss is formed smaller than an inner diameter of the boss relief.

[0037]

As described above in detail, according to the first aspect of the present invention, it is possible to prevent the molding failure of the insulating substrate and to assemble the wiring board assembly reliably.

According to the second aspect of the present invention, the wiring board assembly can be assembled more reliably. According to the third aspect of the present invention, the wiring board assembly can be reliably assembled. Further, generation of abnormal noise due to rattling of the bus bar can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an electric junction box that houses a wiring board assembly according to an embodiment.

FIG. 2 is a cross-sectional view of a main part, similarly showing an electric junction box.

FIGS. 3A and 3B are cross-sectional views showing a process of forming an insulating substrate.

FIG. 4 is an essential part cross-sectional view showing an electric junction box in another example.

FIG. 5 is a sectional view showing an electric junction box according to another example.

FIG. 6 is a cross-sectional view showing an electric connection box according to the related art.

FIG. 7 is a cross-sectional view showing a problem of the related art.

FIG. 8 is a cross-sectional view showing a problem in forming an insulating substrate of the related art.

[Explanation of symbols]

19 ... wiring board assembly, 24, 25, 26, 27 ... insulating substrate, 28, 29, 30, 31 ... bus bar, 36 ... recess,
38, 39, 40, 41 ... tabs as terminal pieces, 46,
47, 48 ... boss, 49, 50, 51 ... tip, 52,
53, 54 ... insertion hole, 55, 56, 57 ... boss escape,
58: tapered surface.

Claims (3)

[Claims] A boss for caulking is formed on an insulating substrate, which is a resin molded product, and a boss relief for accommodating the tip of the boss is formed on another insulating substrate laminated on the insulating substrate. Then, by inserting the boss into an insertion hole formed in the bus bar located between the two insulating substrates and caulking, the bus bar is fixed to the insulating substrate, and the insulating substrate and the bus bar are connected to each other. The assembled wiring board assembly, wherein the boss relief is recessed so as to gradually become deeper from the outer peripheral part toward the center part. 2. The wiring board assembly according to claim 1, wherein an outer peripheral portion of a bottom surface of the boss relief has a tapered surface. 3. A method according to claim 1, wherein a recess for accommodating a bus bar having a terminal piece in a part thereof is provided in said insulating substrate, and a depth of said recess is equal to a thickness of said bus bar. The wiring board assembly according to claim 2.